Sewer cleaning rod turning machines of the type described herein are comprised of a motor, usually an internal combustion motor such as those used in lawn mowers, which operates a drive shaft through a transmission and gear box. The rod turning machine is connected to the end of a long sewer cleaning rod formed of multiple sections of rods joined end to end, which are pushed into a sewer until they reach an obstruction. The rod turning machine is then started and the shift lever operated to stop or start rotation of the sewer cleaning rods. The shift lever permits clockwise or counter-clockwise rotation and has a central neutral position. The opposite rotational directions are controlled by moving the shift lever to either side of neutral.
When cleaning a sewer pipe using the rod turning machine, two workmen are required. One workman stands at an opening to a sewer to push rods into the sewer pipe, while another workman operates the sewer rod turning machine. A problem with these types of devices is that extreme care must be used to avoid too much slack in the rods and too much torque to be built up in the rods. When too much torque builds up with slack permitted between the entrance to the sewer and the connection of the rods to the rod turning machine, the rods can twist and loop. Permitting this to happen can result in dangerously flailing rods and must be avoided. Therefore, it is imperative that the sewer rod turning machine never be left unattended while the shift lever is in an operational position.
With present rod turning machines the shift lever, when positioned to rotate the sewer rods in either direction, will remain in that position and the operator must physically return the lever to neutral. It would be advantageous if the shift lever would automatically return to neutral except when held in an operational position to the right or left of neutral by the operator.
Therefore, it is one object of the present invention to provide a safety device for returning the shifting lever of a sewer rod turning machine to neutral whenever the operator releases the shift lever and leaves the machine.
Another object of the present invention is to provide a safety device for a sewer rod turning machine which is simple and easy to install on existing rod turning machines.